Communism 18 Political doctrines 15 Capitalism 12 Revolutionary movements 9 Working class 9 Economics 7 Imperialism 7 Political parties 7 Cultural anthropology 6 Colonialism 5 Economic and social development 5 Labour movements 5 Political history 5 Political leadership 5 Socialism 5 Ethnic groups 4 Liberation movements 4 Logic 4 Marxism 4 Political movements 4 Social structure 4 Decolonization 3 Economic systems 3 Ethnic discrimination 3 Labour relations 3 Military strategy 3 Philosophy 3 Political conflicts 3 Political philosophy 3 Political sociology 3